Regenerative Injection Laryngoplasty With Scaffold-Forming Oligomer and Autologous Motor Endplate-Expressing Cells: A 6-Month Porcine Study.

OBJECTIVE: Injection laryngoplasty is a standard-of-care intervention for unilateral vocal fold paralysis (UVFP), offering minimally invasive medialization with limited durability. We evaluated a regenerative injectable approach integrating an immunotolerant scaffold-forming collagen (Oligomer) with autologous motor-endplate expressing (MEE) cells to support long-term augmentation and neuromuscular recovery. STUDY DESIGN: Porcine UVFP model. SETTING: Translational research laboratory. METHODS: Twelve Yucatan minipigs underwent right recurrent laryngeal nerve transection. Autologous muscle progenitor cells were isolated, differentiated, and induced into MEEs. Approximately 1 month after denervation, Saline, Oligomer, or MEE+Oligomer was injected into the paralyzed vocal fold. Outcomes were assessed through 6 months using videolaryngoscopy and acoustic vocalization analysis. Neuromuscular function was evaluated at baseline and 6 months using laryngeal electromyography (L-EMG) and laryngeal adductor pressure (LAP). Larynges were also harvested for volumetric ultrasound, histology, and gene expression analyses. RESULTS: All injections were well tolerated, with no evidence of foreign body response. Oligomer and MEE+Oligomer produced persistent augmentation, with MEE+Oligomer demonstrating laryngeal adductor muscle volumes statistically similar to contralateral controls at 6 months. Both treatments improved vocalization outcomes, and MEE+Oligomer was associated with greater neuromuscular function, as indicated by improved stimulated vocal fold adduction, L-EMG activity, and LAP responses. Histological analysis demonstrated identifiable scaffold integration with preservation of muscle morphology. CONCLUSION: In a porcine UVFP model, scaffold-forming Oligomer provided persistent, immunotolerant augmentation with sustained voice improvement. MEE incorporation supported enhanced neuromuscular function consistent with improved reinnervation. This regenerative injection laryngoplasty strategy integrates structural and biological mechanisms to address both mechanical and physiological deficits following UVFP.